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Accurate distance measurements and unbiased cosmological constraints from Type Ia supernovae (SNe Ia) rely on proper correction for host-galaxy dust reddening that may attenuate the observed SN brightness. A correction is made by comparing observed and intrinsic color comma and using a reddening law to determine extinction. This procedure is nontrivial since a SN.s intrinsic color correlates with its luminosity in a manner nearly indistinguishable from the effects of dust reddening at optical wavelengths. The current standard for measuring SN distances treats both fainter-redder relations as a single SN color law. This simplification introduces a bias that depends on the relative contribution of each component. If dust properties change with galactic environment or redshift comma equation-of-state parameter measurements may be biased by up to virgul6%. This issue is currently SN cosmology.s largest systematic uncertainty and if not addressed will prevent future cosmology experiments from meeting their goals. The path to breaking the degeneracy between SN color and dust reddening is to extend observations to the UV and NIR comma where the dust and intrinsic color comma respectively comma dominate the observed color. We propose to image 100 SNe across 2 UV comma 1 optical comma and 4 NIR bands in a single orbit each at a phase in a SN.s evolution where the observed color scatter is small and is late enough to use non-disruptive ToOs. Simulations indicate this sample will be sufficient to constrain the environmental dependence of the dust law and reduce the size of dust-color-related systematic uncertainties to be subdominant even for future cosmological analyses with the Nancy G. Roman Space Telescope.